Ian Fleming, the author of the James Bond novels, once said, "A gentleman's choice of timepiece says as much about him as does his Saville Row suit." Watches have long been a fashion statement for men and women for centuries, and many of us still hold onto those collectible watches despite our tendency to now use our cellphones to check the time. But we might not always want to keep the antique watches, such as pocket watches, we have around the house and instead trade them in for some much-needed cash. How can you tell if you have a valuable...